Rubber safety socket



Nov. 6, 1934. L. J. MCPARTLIN El AL RUBBER SAFETY SOCKET Filed April 16,1930 ATTORNEYS Patented Nov. 6, 1934 PATENT OFFICE RUBBER SAFETY SOCKETLloyd J. McPartlin and Henry v. Harding, Detroit, Mich.

Application April '16, 1930, Serial No. 444,709

6 Claims.

This invention relates to a rubber safety socket especially adapted fortemporary use in repeatedly diverse locations, as for example, in theillumination of a partially finished building, and a has for its objectan improved organization of parts adapted to'permit the convenient andsafe handling, installation, and removal of a string or series ofelectric light bulbs by means of which it is desired to temporarilyilluminate a selected area and wherein the incomplete state of the'buildings installation, such as its wiring system, precludes reliancethereon as a means of securing the desired illumination. Both the safetyof the device as regards handling, and its durability under more or lessrough usage, as well as its easy adaptation to the "support of suchdevices or series in multiple or parallel lines, from a single wire orother support, are purposes to which our improved construction readilylends itself.

In the drawing:

Figure 1 is an elevational view of a single rubber armored socket, withportions of a currentlit carrying cable eirtending from either sidethereof.

Figure 2 is a largely sectional elevational view of the constructionshown in Figure 1.

Figure 3 is a sectional elevational view taken along the line 3-3 ofFigure 2. w

Figure 4 is a small scale elevational view of a string or series oflighting units, the several bulbs of which are designed to receive theirilluminating current from a single easily detached terminal.

A represents a cut-in plug, whose terminal prongs are adapted to beinserted inthe corresponding recesses of any suitable source ofelectrical energy, and B represents a current-carrying cable leadingtherefrom, the range of selection-as to its length being indicated bythe broken portion B. Between two adjacent portions or sections of thiscablethereisacut-away portion as regards the insulating cover D, theremoval of which leaves the wires E and F exposed for connection to theterminal wires G and H leading respectively from connection with theshell of the bulb socket K and from the disc J, which forms the top endof the bulb socket K; the contact leaf piece L of the disc J is adaptedto be engaged in the usual manner by the inner end of the threaded baseor plug. Soldering orother equivalent means for uniting the terminalcords G and H with the current-carrying wires E and F are shown at M.

With the parts as thus far described adequately assembled in anelectrical sense, there is positioned enclosingly about them, includingthe sides of the threaded socket K, a mass of rubber or equivalentinsulating material whichis also made to surround the ends of the cablesheathing which have not been removed, as shown at N. Before the,positioning of this rubber mass about these parts and before thevulcanization thereof, however, a generally U-shaped cord 'orwire P isalso positioned in inverted position with relation to the parts thus fardescribed with its knotted ends, as Q, extending well down into the massor body of the surrounding rubber or other insu lating material, andwhen the vulcanization of the latter has been completed, the legs ofthis U-shaped piece form the backbone or reinforcement of an upstanding*rib, as R, which may be tapered off as shown elevationally in Figure 1,(ll to graceful union with and about the ends of the insulated cableelements B and C, and through the topportion of this upstanding rib, areinforcing metal eyelet, as S, is preferably placed in a positionwithin, that is to say, below the middle portion of the invertedU-shaped piece M; thus when the vulcanization of the protective rubbermass has been completed, this eyelet S, inte- V grated with the rubber,constituting the rib R,

furnishes a means through which a supporting cord or wire may be strungor through which the end of a wall hook or the like may be passed toeffect the support of a series of these elements, such as Figure 4illustrates, in desired relation to the space to be illuminated. Whetherthe support be afforded by a wire, hooks, or any other selected means,the insulation of the currentcarrying parts is at all times so completethat. the individual sockets can be handled with entire safety, and yetthe weight of the several sockets and their feeding wires or cables issupported by a part of the rubber structure as a whole, which 'isreinforced externally of the eyelet S by the passage thereover of theinverted portion of the U-shaped member M. I

It will thus be seen that whether a single string of lights besupported, as illustrated elevationally in Figure 4, or whether asuitably spaced group of such lights arranged in parallel or otherrelation, and each of the general character shown in Figure 4, beemployed, the illumination of the space or areadesired may be executed,as for example for the installation of a tile or wooden floor over theI-beam and cement structure of a building skeleton, without relianceupon the per manent wiring system of the building, which may not have asyet been installed. When the requirement for illumination of the spacein question is at an end, the parts, whether hook or wire-supported, canbe easily taken down without injury or danger, for removal to aninstallation in another space, the terminal plug A being then placed incontact with what terminal may then and there be available.

The most frequently resorted-to use of the apparatus herein disclosedis, of course, illumination, and for the sake of clarity we have sospoken thereof in the foregoing description; it should be understood,however, that the socket terminals mentioned are equally adaptable tothe taking off of current at selected points for other power users, suchas the actuation of small electrically driven drills, electric solderingirons or the like.

What we claim is:

1. In a safety socket, in combination with a shell portion for thereception of a plug base, a current-carrying cable from a selectedportion of which the insulating covering has been removed for, theelectrical connection with the wires thereof of the terminal connectionsof said shell portion, a mass of yieldable insulating materialpositioned about the otherwise exposed portions of the elements thus farrecited, and means anchoringly embedded in said mass and extending abovean aperture in the upper portion thereof whereby the strain incident tothe suspended support of the recited parts is distributed throughrelatively remote portions of said insulating mass.

2. In combination, a lamp socket, yieldable in sulating meanssurrounding said socket and including a bore, and inextensible means,substantially co-planar with the longitudinal axis of said socket, atleast partially encircling said bore and imbedded in the insulatingmeans.

3. In combination, a lamp socket, yieldable insulating means surroundingsaid socket and including a bore, and inextensible means at leastpartially encircling said bore and imbedded in said insulating means ata distance-from said bore for distributing through said insulating meansstresses applied thereto in a direction parallel to the longitudinalaxis of said socket.

i. In combination, a lamp socket, current carrying connections to thesocket, yieldable insulating means surrounding said socket and saidconnections and including a bore, and inextensible means, substantiallyco-planar with the longitudinal axis of said socket, at least partiallyencircling said bore and imbedded in. the insulating means for adistance from said bore for distributingthrough said insulatingv meansstresses applied thereto at said bore.

5. In combination, a lamp socket, yieldable insulating means surroundingsaid socket and including a bore, and inextensible means, substantiallyco-planar with the longitudinal axis of said socket, at least partiallyencircling said bore at a distance therefrom, and imbedded in theinsulating means for a distance extending from said bore, fordistributing through said insulating means stresses applied thereto in adirection parallel to the longitudinal axis of said socket.

6. In combination, a plug-receiving socket, yieldable insulating meansassociated with said socket and having an aperture therein, the axis ofsaid aperture lying at an angle to the longitudinal axis of said socket,and anchoring means embedded in said insulating means adjacent saidsocket and extending around said aperture, whereby stresses applied tosaid insulating means at said aperture are distributed throughout saidinsulating means.

